Retba: the pink lake
Known by Lac Rose (“pink lake” in French), Lake Retba in Senegal appears to have been the victim of a chemical spill but, fortunately, its color is not altered. Situated on the Cap Vert peninsula in the north of the country, the lake owes its pink color to a very particular type of algae: dalaliella salina.
This micro-something halophile, usually found in areas with high concentration of salt, becomes pink during the dry season. The high concentration of salt in this lake means that the lake is an important place for local industry but, like the Dead Sea, we can float on it.
Dunaliella saline is known for its anti-oxidant activity and can create plenty of carotenoids. Thus, it is often found in cosmetics and dietary supplements. In fact, and to protect themselves, many of the workers who collect salt from this lake are smeared with shea butter to prevent tissue damage.
The bizarre features of this lake and its location near Dakar, the capital of Senegal, have turned the place into a tourist spot. Good for the local economy but not so much for the environment.